What Causes Achilles Tendonitis in Runners and Active Adults?

A cropped shot of a man with achilles tendonitis holding his ankle

A sharp ache near the back of your heel. Morning stiffness that eases with movement. Pain that flares up after a run you’ve done a hundred times before. For runners and active adults, these are often the first signs of Achilles tendonitis.

At Union County Orthopaedic Group, patients struggling with Achilles tendonitis benefit from decades of professional insight paired with genuinely attentive care. Our team of board-certified and board-qualified physicians makes it easier to get answers without long waits or complicated scheduling.

What Is Achilles Tendonitis?

The Achilles tendon connects the calf muscles to the heel bone and plays a major role in walking, running, and jumping. Achilles tendonitis occurs when this tendon is irritated or inflamed, usually from repeated stress rather than a single injury. This condition is especially common among runners, weekend warriors, and people whose jobs or hobbies keep them on their feet.

Common Causes of Achilles Tendonitis

Several factors can contribute to Achilles tendonitis, often working together rather than alone. Potential causes include: 

  • Overuse and training errors: These may include rapid increases in mileage or intensity, adding hills or speed work too quickly, and insufficient recovery time.
  • Tight or weak calf muscles: Limited calf flexibility or strength can place extra strain on the Achilles tendon during activity.
  • Improper footwear: Shoes that lack support, have worn-down heels, or aren’t suited to your activity can alter how force is distributed through your ankle.
  • Biomechanical issues: Flat feet, high arches, or abnormal walking and running patterns can increase stress on the tendon with each step.
  • Age-related changes: As we get older, the Achilles tendon naturally loses some elasticity, making it more vulnerable to irritation during repetitive motion.

Why Early Attention Matters

Ignoring early symptoms can lead to chronic pain or even tendon degeneration. Addressing discomfort promptly often allows for simpler treatment options and a quicker recovery.

Depending on the severity, care may include activity modification, targeted physical therapy, stretching and strengthening programs, supportive footwear or orthotics, and other non-surgical approaches designed to reduce strain on the tendon.

Schedule an Evaluation Today

If heel or ankle pain is slowing you down, early care at Union County Orthopaedic Group can make a meaningful difference. Book an appointment online or give us a call at one of our five locations: 

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Urgent care 3pm-6pm

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